Zebrafish larvae readily absorb compounds from the surrounding water, which is a great advantage when it comes to determining the effects of certain drugs or other substances. For example, they are an ideal subject when testing novel anticonvulsants or proconvulsants in epilepsy research.
Zebrafish larvae have the great advantage of being small enough to test in multi-well plates, making them suitable for high-throughput screening. A controlled testing environment allows for effective and efficient protocols.
An observation chamber offers just that. The DanioVision Observation Chamber provides a complete testing environment: it contains all necessary hardware on the inside, keeping everything else out so you are in control over the experimental conditions. Its innovative design guarantees a reliable image for tracking each individual larva.
Screening compounds benefits greatly from 96-well plate setups, as this allows for high-throughput testing. DanioVision is a great tool for accommodating such research.
“Exposing 2 to 4 dpf fish to moderate concentrations of water-soluble proconvulsants, such as pentylenetetrazol (PTz), is sufficient to dramatically increase locomotion that can very easily be measured using the DanioVision system”, according to Richard Baines (University of Manchester, UK).Light stimuli are used in zebrafish research to investigate anxiety behaviors and circadian rhythmicity. For example, intensity and timing of white light can be controlled to induce a startle response or mimic a day-night cycle. Research indicates that zebrafish are also sensitive to different wavelengths. In other words: they can color discriminate.
Zebrafish are able to discriminate between different wavelengths of light; they can see color. In their overview of color processing in zebrafish, Meier et al. describe several studies in which a preference was found for blue/short wavelength light in both adult and larval fish.
In contrast, a few studies report zebrafish preferences for other colors. For example, Ahmad and Richardson describe that the larvae in their study showed a preference for orange and green, and avoided yellow, blue, red, and black.
Light conditions can also influence the development, growth, and survival of zebrafish. The degree of effect depends on the wavelength (color) of the light. In their study, Villamizar et al. found that hatching rate was higher under blue and violet light. Also, the total length of the zebrafish was greatest when raised under blue, violet, and white light. On the other hand, red light exposure led to less feeding and poor survival rates.
These findings open up new opportunities to test learning, memory, anxiety, and more. For example, Li et al. found that zebrafish under acute or chronic alcohol treatments changed their color preferences. These results suggest that alcohol can disturb visual-based learning and memory in adult zebrafish.
Also, Pieróg et al. found that treatment with alprazolam affected zebrafish behavior in different color zones. Specifically, zebrafish spent more time in the red zone compared to yellow or green, and in the yellow or blue compared to green.
Color preference testing requires the use of different colors within the testing arena. For example by using colored sleeves in a T-maze or cross-maze setup when working with adult zebrafish.
To create colored light conditions, you can use the DanioVision Toplight Unit in studies with zebrafish larvae. This unit has three different colors of LED lights, so you can measure and compare animal behavior under different wavelengths.
Meier, A.; Nelson, R.; Connaughton, V. (2018). Color processing in zebrafish retina. Frontiers in Cellular Neuroscience, 12, 327.
Ahmad, F.; Richardson, M. (2013). Exploratory behaviour in the open field test adapted for larval zebrafish: impact of environmental complexity. Behavioural Processes, 92, 88-98.
Villamizar, N.; Vera, L.M.; Foulkes, N.S.; Sánchez-Vázquez, F.J. (2014) Effect of Lighting Conditions on Zebrafish Growth and Development. Zebrafish, 11(2), 173–181.
Li, X.; Li, X, Li, Y.-X.; Zhang, Y.; Chen, D.; Sun, M.-Z.; Zhao, X.; Chen, D.-Y.; Feng, X.-Z. (2015) The Difference between Anxiolytic and Anxiogenic Effects Induced by Acute and Chronic Alcohol Exposure and Changes in Associative Learning and Memory Based on Color Preference and the Cause of Parkinson-Like Behaviors in Zebrafish. PLOS ONE, e0141134
Pieróg, M.; Guz, L.; Doboszewska, U.; Poleszak, E.; Wlaź. (2018). Effects of alprazolam treatment on anxiety-like behavior induced by color stimulation in adult zebrafish. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 82, 297-306.